Found a good deal on this and wanted to upgrade. You think I could make this fit? 350 with holley street warrior carb. 3rd gen’s aren’t listed but didn’t know if anybody here tried one of these in their 3rd.

 

I don't think that radiator is going to fit. I have a 1987 IROC and I just went out in the garage and measured the radiator support from side to side and it measured 31". A 33.25" wide radiator isn't coming close to fitting in there.

In addition, I'm one of those people who haven't had good luck with Griffin radiators. I've had two that started leaking in a short amount of time. No more Griffins for me. That's my 2 cents!

 

Thanks for the advice!! I think i’ll follow suit because i’ve heard bad things about griffins before. Any other recommendations instead?

 

You didn't say if there is something wrong with the radiator you have. What about a stock radiator with LS fans. It would be a lot cheaper and work great.

 

I have a Griffin universal radiator in my car 15.5" x 27" x 3" and it's awesome. It doesn't leak whatsoever and cools my turbo LS no problem

 

My Griffin doesn't leak...

 

BBCSwap asks a great question. What is wrong with your current system that makes you want to change the radiator and fans? The reason this is a good question is if you have an engine overheating problem, it may not necessarily be due to your current radiator or fan(s).

 

Yeah, the engine does get a little warmer than I would like. And the stock radiator is probably fine, but the fan on it is some junk that apparently came out of a jeep. I figured If i’m gonna upgrade the fans then I might as well do the rad at the same time but If you guys think the stock rad will be good with better fans then I’ll try that.

 

What engine temperature are you seeing at highway speed (above about 35-40mph) and what is the engine temperature during a prolonged idle, vehicle not moving? AC on or off. What is your ambient temperature?

 

Highways speed it’s pretty good at 190-200ish when it’s 90°+ outside. My problem is my commute to work has a lot of red lights, so it’s gotten as hot as 230° when idling at red lights. I recently got the AC to work so i’m sure that’s making it warmer. I just want it to stay cooler while At red lights so I thought a bigger rad with better fans would be a good upgrade considering how long i’m stuck idling. I did add a 160° thermostat as the car didn’t have one in it when I got it. Which i’m sure it’s just staying open the whole time as it’s not gonna cool down to that temp while the weather is like this. I also bypassed the heater core because it was leaking.

Edit: this is also my first V8 so I am learning a lot, I’m used to driving my 8th gen civic for the past 8ish years. This is a completely different ballgame for me.

 

Yeah, that 160F thermostat isn't going to do much for you. I've read on this website that the stock fans don't even come on until a high temperature like what you're seeing during stop and go driving. Most of us car guys are uncomfortable with these higher temps but Chevrolet seems to be good with the high temps. I'm with you; I'd rather see lower temperatures, even with my LS engines.

You don't have a radiator problem. Your car is staying cool at highway speeds which tells me that your radiator is good and you have your airdam in place under the front of the car. The bypassed heater core shouldn't be affecting anything.

If the ECU isn't commanding the fans (or more than likely, the second fan) to come on until about 235F, then the engine is just going to run warmer unless you can reprogram the ECU. Right now, if you install the most powerful radiator fan in the world (maybe the Spal, brushless, 18" PWM fan out of a 6th gen Camaro or the Delta PAG 18" PWM fan) it still wouldn't come on until your ECU told it to turn on. OK. Your ECU can't generate the required PWM (pulse width modulated) signal but I'm just trying to make a point here.

I just noticed that you wrote: "but the fan on it is some junk that apparently came out of a jeep."
It sounds like you've got a single fan. Do you know if your car came with a single fan or two fans? My IROC was stock with two electric fans. My 2002 WS6 Trans Am has two fans from the factory.

At this point, like BBCSwap said, I recommend keeping your radiator and sourcing LS1 fans from a 4th gen F body. These seem to be popular, fit and your ECU should be able to control them since they're old school, brushed, non-PWM fans. I wouldn't recommend aftermarket chinesium fans. They're junk! Get an OEM fan assembly. You can still buy the actual fan motors from Rockauto: GM GENUINE 158404

I purchased a pair of these genuine GM motors a while back just to have on hand in case one or both of my WS6's fan motors gives up the ghost.

 

Great info! I completely forgot to mention that the previous owner wired up a switch to the fan below the steering wheel, so it can stay on all the time. It is a single fan from some kinda jeep is what he told me. It was originally a 5.0 tbi but has a 350 swapped in. Previous owner rebuilt the trans and added a trans cooler in front of the rad. I definitely think adding a dual fan would make a ton of difference. Also has a switch right there for the little holley fuel pump he put in it. I imagine the car originally had 2 fans but for whatever reason was replaced with a single one during its life.

 

I'd look for an OEM, 4th gen F body fan assembly. I'd also look and see if your car's original fan wiring is still in place. I don't like wiring like the previous owner did. If you can get your ECU to run the fans, it'll be cleaner and you won't have to think about it. The ECU may have to be reprogrammed to make the fans come on at a lower temperature. I don't mess with OEM ECUs. I've got Holley Dominators for my LS swapped Fox coupe and (in progress) LS7 swap IROC.

***IF*** it originally had two fans controlled by the ECM and you can find the connectors, you should be able to hook up the 4th gen fans without too much trouble. Connectors may be different but that's not that difficult to deal with.

 

I’ll try and see if the original wiring is still there tomorrow. At work today and the cars at home. Would the ECU have been swapped if it had a 350 put in it? This is all new to me.

 

I would think so but people do all kinds of things. Did you tell us what year your car is?

 

I'm guessing it's a 1989 by your screen name.

 

It’s an 89 RS

 

Does your car still have a TBI system? If so, it sounds like you've got a Frankenstein setup. I ***think*** that all 350s were TPI. Mine was. I don't think that my TPI ECU would be able to run your TBI engine. I'm guessing the previous owner might have used the 305 TBI ECU. Somebody with way more 3rd gen knowledge will have to chime in on this.

You could also search in the "DFI and ECU" forum on this website.

 

So originally it was a 305 tbi. It has a 350 with a holley street warrior 4 barrel carb. It’s 110% a frankenstein but it’s my frankenstein. I’m not sure what the 350 came out of , probably a truck or something

 

Oh. Ok. The 350 engine isn't even managed by the ECU.

I'm wondering if your car's original ECU is still in place under the dash on the passenger side. If it is, I wonder if there is any wiring connected to it. If so, can it do anything like control fans if it is not controlling the engine. I'm guessing not because it would need sensor inputs for thing like engine coolant temperature.

Like I said in my last post, someone with way more 3rd gen knowledge will need to comment.

You other options would be to wire the 4th gen fans like the previous owner did or for more automation, you could purchase an aftermarket controller to control the fans. In my previous Foxbody Mustang back around 2007, I installed an old school, mid 1990s Lincoln MKVIII electric fan. I purchased a Delta Current Control aftermarket controller to manage the fan. It worked beautifully!

 

Well I’m pretty sure i saw the ECU in there when I was poking around looking for the heater core. I’m not sure what all would still be connected to it. The car has aftermarket gauges where the radio would be that i’m assuming just go straight to where the original sensors would be. I most of the gauges in the cluster don’t work except voltage, and the gas gauge jumps from 3/4 when it’s full to 1/4 when it’s about empty. It also has a switch for the ignition, but you have to turn the key on for power to the fuel pump and fan switches.

 

It sounds to me like the ECU is just sitting in it's spot doing nothing. You'd have to either wire the 4th gen fans the way the previous owner did or buy an aftermarket controller to control the fans.

You'll want to take a real good look at how the PO wired things up. Most people aren't very good at electrical. I'd assume the worst was done and plan on fixing the bad. If you have inadequate size wiring and hackjob connections, even good fans aren't going to operate very well.